The present invention relates to a transmission cable for use with an ultrasonic device such as an ultrasonic machining device and the like and, more particularly, to a transmission cable of the type that comprises a plurality of fine wires covered with a tubular member.
The conventional transmission cable used as a transmission medium for an ultrasonic device has been made of a single thick metallic wire. However, this kind of cable has such drawbacks that it is not always satisfactory in its way of transmitting ultrasonic oscillations efficiently to a terminal machining tool coupled to the cable and, moreover, it lacks flexibility and is therefore inconvenient for carrying out ultrasonic machining operations with the tool.
To overcome the above mentioned disadvantages of the conventional transmission cable, the present inventors have found, after experiments, that by use of a transmission cable comprising a plurality of fine metallic wires covered with a flexible tubular member, preferably that which is filled with a liquid, the ultrasonic oscillations effected by the ultrasonic device can be transmitted more efficiently than otherwise to the terminal machining tool coupled to the cable and further that this type of cable, since the tubular member is made of a flexible material, is easy to handle and therefore convenient for carrying out ultrasonic machining operations.